Lubrication 1 Flashcards
Correct lubrication reduces?
Friction
Friction between moving surfaces is grouped into three main types.
Rolling, Sliding, Fluid
Bearings that use rolling members to reduce friction are called?
Anti friction bearings
The force that causes unlike materials to stick together is called? SLE/IP
Adhesion
The force that causes like materials to stick together is called? SLE/IP
Cohesion
Resistance to flow is defined as the?
Viscosity
Heating oil causes its viscosity to?
Decrease
During start up, a rotating shaft forms an?
Oil wedge
The efficiency of an oil wedge depends upon?
Shaft surfaces, Clearance between between surfaces, operating temperature.
Over lubricating threaded holes or screws may cause?
Hydraulic lock
Additives an inhibitors are introduced into oils to control?
Air, water, and load
Petroleum and vegetable oils react with oxygen, this is called?
Oxidation
The ability of a petroleum oil to seperate from water upon standing is called? SLE/IP
Demulsibilty
The ability of a petroleum oil to mix with water such as machine shop cutting fluid is ? SLE/IP
Emulsibility
Additives that are used for heavy loads or shock load conditions are called?
Extreme pressure additives
Oil lubrication is applied in two main types of systems?
Once through and enclosed
The above drawing shows?
Oiler rings
The most commonly used method of lubrication in an enclosed gear system is?
The splash method
The recommended method for lubricating high speed bearings and high velocity roller chains is the?
Oil mist method
The above drawing shows 2 lubrication systems, whats the most likely application for pump B?
Multiple lubrication points
Greases are usually made by thickening lubricating oils with?
Soap
Greases recommended for water resistance and high temperature are called?
Lithium and barium soap
The most common additive for increasing the anti wear capacity of a grease is?
Molybdenum disulfide
The temperature at which grease becomes fluid enough to drip is called the ?
Dropping point.
On low speed applications with extreme conditions of moisture, dirt, or poor sealing, it is recommended to fill the bearing housing with grease to the?
Full mark
The above drawing shows a?
Spring compression grease cup.
When lubrication open gears, you should consider?
Gear materials, Environment, Temperature.
The type of lubrication for enclosed gears depends upon?
Load, Operating speed, Operating temperature.
When the pressure between meshing gear teeth is too high, the oil film?
Will fail
The oil bath bearing should not exceed the?
The mid point of the lowest rolling member.
In the above diagram is the oil bath acceptable?
yes
One advantage of using grease as a lubricant is?
It provides better start up protection after short periods of down time.
The advantages of using oil as a lubricant are?
Lubricates well at high to very high speeds, Can be used as a heat exchange medium, Can be removed easily from the housing, All of the above.
The main purpose of using cutting fluid during machining process is to?
Cool the work piece by reducing friction.
Straight cutting oils may be classified as?
Active or in active.
Oils that may be mixed with water and used as cutting solutions are called?
Emulsifiable
Chemical oils that are soluble and contain rust inhibitors are generally used for?
Grinding
When handling lubricants, it is always advisable to? IP
Avoid skin contact by wearing gloves an aprons etc, Avoid breathing mist or fumes, Wash hands and arms fully at the end of each shift, All of the above
When doing lubrication preventative maintenance, the millwright should look for?
Low levels or lack or lubricant, Heat or smell of burn oil, Excessive noise in drive units, All of the above
“Active” oils react with ?
Non ferrous metals
Which of the following additives would be used to control the action of water in oil?
De-emulsifying and anti corrosion.
The four main points to consider when selecting a lubricant is the clearance between moving parts, the operating temperatures, the weight on the moving parts and the?
The rubbing velocity
The lowest temperature that an oil will run is its pour point, the lowest temperature a grease will run is called?
Dropping point.
A certain machine has a operating temperature that is so high that the oil life is short. the correct approach to the problem is to?
Troubleshoot, lower the machine temperature through engineering, adding systems or upgrading.
As a general rule, when the RPM of a rotating part is increased, the viscosity of the oil used will?
Be decreased
The general lubricant used when drilling cast iron is?
No lubricant…. cause it has graphite in it
Which of the following is the hardest or stiffest grease?
Number 6
What are some common cause of lubrication problems in anti friction bearings?
Contaminated bearing, not enough lubricant, to much lubricant to often, all answer below
Which of the following types of gear oil would be most probably recommended for the gear case of an over head crane?
Gear oil with an EP additive.
The oil additive that retards the chemical decomposition of an oil is ?
Anti-oxidant.
